T atomic_fetch_add(volatilestd::atomic<T>*obj, typenamestd::atomic<T>::difference_typearg)noexcept; (2)(since C++11) template<classT> T atomic_fetch_add_explicit(std::atomic<T>*obj, typenamestd::atomic<T>::diff
T fetch_add( T arg, std::memory_order order = std::memory_order_seq_cst ) volatile; (2) (since C++11) (member only of atomic<T*> template specialization) T* fetch_add( std::ptrdiff_t arg, std::memory_order order = std::memory_order_seq_cst ); ...
T fetch_add( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; T fetch_add( T arg, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; 仅为atomic<T*> 模板特化的成员 (2) T* fetch_add( std::ptrdiff_t arg, std::memory_order or...
T fetch_add(T arg,std::memory_orderorder= std::memory_order_seq_cst)volatilenoexcept; (2)(since C++11) member only ofatomic<T*>partial specialization T*fetch_add(std::ptrdiff_targ, std::memory_orderorder= std::memory_order_seq_cst)noexcept; ...
#include <iostream> #include <thread> #include <atomic> std::atomic<long long> data; void do_work() { data.fetch_add(1, std::memory_order_relaxed); } int main() { std::thread th1(do_work); std::thread th2(do_work); std::thread th3(do_work); std::thread th4(do_work); ...
res = std::atomic_compare_exchange_strong_explicit(&a0, &expected, desired, std::memory_order_relaxed, std::memory_order_relaxed); assert(res && expected == 3 && desired == 2 && a0 == 2); a0 = 1; val = std::atomic_fetch_add(&a0, 2); ...
它首先指出std::atomic可能没有与T相同的大小或对齐方式: 当我们设计C++11原子操作时,我错误地认为可以使用以下代码对未声明为原子的数据进行半可移植的原子操作: int x; reinterpret_cast<atomic<int>&>(x).fetch_add(1); 如果原子和整数的表示方式不同,或者它们的对齐方式不同,那么这显然会失败。但是我...
atomic_exchange_explicit<>() (std::shared_ptr) (C++11 起)(C++20 中弃用)atomic_fetch_add<>() (C++11 起)atomic_fetch_add_explicit<>() (C++11 起)atomic_fetch_and<>() (C++11 起)atomic_fetch_and_explicit<>() (C++11 起)atomic_fetch_or<>() (C++11 起)atomic_fetch_or_explicit<>...
std::atomic<int> val(10); val++; // 原子操作,线程安全 val.fetch_add(100); // 等同于 val += 100,线程安全 val.fetch_sub(100); // 等同于 val -= 100,线程安全 val.fetch_xor(10); // 等同于 x ^= 10,线程安全 val.fetch_and(10); // 等同于 x &= 10,线程安全 val.fetch_or...
引用计数操作通过控制块实现,包括增加引用计数(_m_add_ref)和减少引用计数(_m_release)等。 cpp void _m_add_ref() noexcept { __atomic_fetch_add(&_m_use_count, 1, __atomic_seq_cst); } void _m_release() noexcept { if (__atomic_fetch_sub(&_m_use_count, 1, __atomic_seq...